Distonic oxonium and ammonium radical cations. A neutralization-reionization and collisional activation study

1985 ◽  
Vol 107 (26) ◽  
pp. 8059-8066 ◽  
Author(s):  
Chrysostomos Wesdemiotis ◽  
Paul O. Danis ◽  
Rong Feng ◽  
Jacqueline Tso ◽  
Fred W. McLafferty
Keyword(s):  
Collisional Activation ◽  
Radical Cations ◽  
Ammonium Radical

HX-Eliminierung (X = OH, NH2) aus primären ω-phenylsubstituierten Alkoholen und Aminen: Indiz für interne Solvatisierung von Radikalkationen in der Gasphase oder Resultat einer selektiven Aktivierung von CH-Bindungen? / HX-Elimination (X = OH, NH2) from Primary ω-Phenylsubstituted Alcohols and Amines: a Probe for Internal Solvation of Gaseous Radical Cations or the Result of a Selective Activation of CH-Bonds ?

1977 ◽  
Vol 32 (8) ◽  
pp. 880-885 ◽  
Author(s):  
Karsten Levsen ◽  
Heinz Heimbach ◽  
Michael Bobrich ◽  
Johannes Responder ◽  
Helmut Schwarz
Keyword(s):  
Mass Spectrometry ◽  
Collisional Activation ◽  
Radical Cations ◽  
Selective Activation ◽  
First Time

Using collisional activation mass spectrometry the structures of the [M–HX]+• ions (X = OH, NH2) from 5-phenylpentanol-1 (1), 5-phenylpentylamine (2) and 6-phenylhexanol-1 (3) have been established. Contrary to previous results it is shown for the first time that in addition to ionized 1-phenyl-alkenes-1 some other double bound isomers as well as phenylcyclopentane and phenylcyclohexane are formed. The results strongly suggest that the HX eliminations are induced by a selective activation of CH bonds.

Organische Schwefelverbindungen, XXXIII CO2-Eliminierung aus Radikalkationen von Thiolestern in der Gasphase: Intramolekulare Sauerstoff-Wanderung vom (C+3/C+3)-Typ / Organic Sulfur Compounds, XXXIII CO2 Elimination from Gaseous Radical Cations of Thiol Esters: Intramolecular Oxygen Transfer of (C+3/C+3)-Type

1979 ◽  
Vol 34 (2) ◽  
pp. 316-320 ◽  
Author(s):  
Bernd Kohne ◽  
Klaus Praefcke ◽  
Helmut Schwarz
Keyword(s):  
Gas Phase ◽  
Oxygen Transfer ◽  
Collisional Activation ◽  
Radical Cations ◽  
Ester Group ◽  
Reaction Sequence ◽  
Thiol Ester ◽  
Organic Sulfur Compounds ◽  
Thiol Esters ◽  
First Time

Abstract It is shown for the first time that under electron impact conditions an intramolecular oxygen transfer is possible from the thiol ester funtion onto the carbon atom of a second thiol ester group. The reaction sequence is terminated by CO2 elimination and the proposed structure of the resulting product ion is based on 13 carbon labelling experiments and collisional activation mass spectrometry. In addition, some unusual examples of ring contraction processes in the gas phase are reported.

Reactivity Trends in the Gas Phase Addition of Acetylene to N-protonated Aryl Radical Cations

2020 ◽  
Author(s):  
Oisin Shiels ◽  
P. D. Kelly ◽  
Cameron C. Bright ◽  
Berwyck L. J. Poad ◽  
Stephen Blanksby ◽  
...  
Keyword(s):  
Gas Phase ◽  
Ion Trap ◽  
Radical Cations ◽  
Rate Coefficients ◽  
Similar Process ◽  
Ion Molecule Reactions ◽  
Aromatic Radicals ◽  
Polycyclic Aromatic ◽  
Gas Phase Ion ◽  
Type Radical

<div> <div> <div> <p>A key step in gas-phase polycyclic aromatic hydrocarbon (PAH) formation involves the addition of acetylene (or other alkyne) to σ-type aromatic radicals, with successive additions yielding more complex PAHs. A similar process can happen for N- containing aromatics. In cold diffuse environments, such as the interstellar medium, rates of radical addition may be enhanced when the σ-type radical is charged. This paper investigates the gas-phase ion-molecule reactions of acetylene with nine aromatic distonic σ-type radical cations derived from pyridinium (Pyr), anilinium (Anl) and benzonitrilium (Bzn) ions. Three isomers are studied in each case (radical sites at the ortho, meta and para positions). Using a room temperature ion trap, second-order rate coefficients, product branching ratios and reaction efficiencies are reported. </p> </div> </div> </div>

Properties and Reactivity of First and Second Row Hydrides. IV. Interactions Between Hydrides and Their Radical Ions

1993 ◽  
Vol 58 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Rudolf Zahradník
Keyword(s):  
Radical Cations ◽  
Stabilization Energy ◽  
Hydrogen Atom Abstraction ◽  
Type Ii ◽  
Radical Ions ◽  
Reaction Products ◽  
Ion Molecule Reactions ◽  
Heats Of Reaction ◽  
Experimental Values ◽  
Easy Differentiation

The energies and heats of ion-molecule reactions have been calculated (MP4/6-31G**//6-31G** or better level) and compared with the experimental values obtained from the heats of formation. Two main types of reactions have been studied: (i) AHn + AHn+• ↔ AHn+1+ + AHn-1• (A = C to F and Si to Cl), (ii) AHn + BHm+• ↔ AHn+1+ + BHm-1• or AHn-1+• + BHm+1+ (A and B = C to F). In contrast to (i), processes of type (ii) permit easy differentiation between the proton transfer and hydrogen atom abstraction mechanisms. A third type of interaction involves reactions with radical anions (A = Li to F); comparison was made with analogous processes with radical cations. A brief comment is made about the influence of the level of computational sophistication on the energies and heats of reaction, as well as on the stabilization energy of a hydrogen bonded intermediate, a structure which is similar to that of the reaction products.

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